OLED display element has attracted more and more attentions due to advantages such as self-luminescence, being rich-colored, rapid response, wide viewing angle, small weight and thickness, low power consumption, and being capable of achieving flexible display. In addition, a display device with the OLED display elements has a broad application prospect.
The OLED display element has a basic, sandwich-like structure consisting of an anode, a cathode and an organic light-emitting layer between the anode and the cathode. Usually, the anode is thin and transparent, and is an indium tin oxide (ITO) layer having a semiconductor characteristic, and the cathode is a metal layer or a metal oxide layer. In the case that a voltage is applied to the OLED display element, electron holes from the anode may be combined with electrons from the cathode at the light emitting layer, so as to enable the OLED display element to emit light through the anode or cathode. However, due to the limit of its structure, the luminous intensity and the luminous efficiency of the OLED display element are relatively low.